The team at the International Center for Genetic Engineering and Biotechnology (ICGEB) in the northern city of Trieste photographed the structure of nucleic lymphocites with a high-resolution microscopy technique, a statement from ICGEB said.

That the problem regarding AIDS is due to the property of the virus to insert its own DNA into that of the cells that it infects so that it becomes part of their genetic patrimony had been known for some time.

However, how the virus manages to "hide" from therapeutic drugs inside these genes has remained, until now, an enigma, ICGEB director general Mauro Giacca said.

"Since the 2000s there had been databases of tens of thousands of human DNA sequences in which the HIV virus integrated, but for 15 years no one was able to discover what they had in common," he noted.

"We have found that their common characteristic is being in the outer shell of the nucleus in close correspondence with the nuclear pore," Giacca added.

This region, he explained, contains a series of cellular genes characterised by factors that hide the presence of the HIV virus.

In contrast, the virus strongly disfavours the regions in the nuclear lamin-associated domains and other regions located centrally in the nucleus. Therefore, the discovery shows the manner in which it is the very architecture of the nucleus of the lymphocytes and the areas that the HIV virus chooses to localise that assists its concealment, Giacca said.

The breakthrough, which was published on the website of the journal Nature earlier this week, could lead to the development of new AIDS drugs aimed at impeding the virus' integration into these regions by targeting proteins of the nuclear pore.

Since the beginning of the 1980s, when the AIDS epidemic started to diffuse, almost 80 million people have been infected by the virus, according to the World Health Organization (WHO) estimates, but not even one of these has been able to be completely cured.